1. Field of the Invention
This invention relates generally to methods of forming consolidatable resin coated particulate materials in aqueous gels, and more particularly, to improved methods of continuously coating a particulate material such as sand with a hardenable resin composition in the presence of an aqueous gel whereby the resin coated particulate material can be placed in a subterranean formation and consolidated therein.
2. Description of the Prior Art
Methods of continuously forming and transporting consolidatable resin coated particulate materials in aqueous gels have been developed and used heretofore. The methods are particularly useful in treating subterranean formations containing loose or incompetent sands which migrate with hydrocarbons produced therefrom in that the resin coated sands suspended in aqueous gels can be placed in the subterranean formations and consolidated therein. The resulting consolidated, permeable, particulate mass placed between the producing formation and the well bore penetrating the formation prevents the loose or incompetent sands from being carried into the well bore.
The originally developed methods of placing resin coated particulate material into subterranean formations involved the batch mixing of component streams. For example, U.S. Pat. No. 4,074,760 issued Feb. 21, 1978 discloses a method of forming a consolidated particulate mass in a subterranean formation wherein resin coated sand is suspended in a gelled aqueous carrier liquid. The carrier liquid is introduced into a subterranean zone whereby the resin coated sand is deposited and subsequently consolidated therein. The carrier liquid and the resin coated sand are prepared by batch mixing of components.
U.S. Pat. No. 4,199,484 discloses a method of preparing a suspension of a particulate material coated with an epoxy resin in a gelled aqueous carrier liquid wherein the coating of the sand is carried out in the gelled aqueous carrier liquid. The gelled carrier liquid, sand and other components are first combined followed by the addition of the epoxy resin with mixing whereby the epoxy resin coats the sand. Once coating has taken place, the slurry is introduced into a subterranean zone.
More recently, methods of continuously forming and transporting resin coated particulate materials in aqueous gels have been developed and used. For example, U.S. Pat. No. 4,829,100 issued May 9, 1989 discloses a method whereby a stream of gelled aqueous carrier liquid is substantially continuously mixed with particulate material, a resin composition and a surface active agent. The particulate material is continuously coated with the resin and suspended in the gelled aqueous carrier liquid, and a substantially continuous stream of the gelled aqueous carrier liquid containing the resin coated particulate material is introduced into a subterranean zone. The resin on the coated particulate material is then allowed to harden whereby the resin coated sand is consolidated into a hard permeable mass in the formation.
While the methods of continuously forming and transporting resin coated particulate materials in aqueous gels described in U.S. Pat. No. 4,829,100 have been utilized successfully, the surfactants utilized in accordance with the methods are generally incompatible with other surfactants which could be advantageously used as oil-water de-emulsifiers, foaming agents and the like, particularly when polysaccharide gelling agents such as guar gum and derivatives thereof are used.
Thus, there is a need for an improved method of continuously forming and transporting resin coated particulate materials in aqueous carrier liquids gelled with polysaccharide gelling agents including guar gum and derivatives thereof wherein other oil-water de-emulsifying surfactants, foaming surfactants and the like can be included in the carrier liquid.